Even with several decades of IT project management research and practice, there are still issues with keeping projects on time and within budget, with the final product adding value to the project organization. With the overwhelming majority of IT projects involving teams of workers, it is important to take advantage of insights drawn from work within the referent discipline of organizational behavior, and more specifically from work that focuses on teams and team member behaviors. This research focuses on antecedents impacting social loafing that would fall under the category of informal controls. Specifically, our research question is do antecedents identified as important in the Collective Effort Model in team projects have an impact on social loafing? These findings provide a contribution to the theoretical basis for social loafing and potentially lead to a better understanding of how IT project leaders can most effectively influence project processes and outcomes.